1. Field of the Invention
The present invention relates to a system for executing mutual protocol in an electronic communications system, and more particularly to a system of processing, converting and distributing a message in a network hierarchy for a fixed subscriber unit (FSU) in a Broad band Code Division Multiple Access Wireless Local Loop (B-CDMA WLL).
2. Description of the Related Art
Conventionally, a network hierarchy of an FSU and radio carrier station (RCS) in the B-CDMA WLL includes 7 layers according to the Open Systems Interconnection (OSI) model of the International Organization for Standardization (ISO), as shown in FIG. 1. In the first layer L1 PHL/MAC (Layer 1 Physical/Medium Access Control), the FSU comprises a subscriber line interface circuit module (SLIC2) 2, ADPCM/PCM module 4, MAC module 6 and PHL module 8 while the RCS comprises a PHL module 22 and MAC module 24. The second layer L2 DLC (Layer 2 Data Link Control) provides the FSU and RCS with their respective DLC modules 20 and 26. The third layer L3 NWK (Layer 3 NetWork) provides the FSU with a network module 18. The higher layers provide the FSU with a subscriber module 12, retaining module 14, and message conversion and distribution module 16. In addition, the FSU and RCS include lower layer management entities (LLME) 10 and 28.
FIG. 1 illustrates the conventional network hierarchy of the FSU including a message conversion and distribution module 16, which formats a message communicated between the network module 18 and the higher modules (subscriber module 12 and retaining module 14) to distribute the formatted message among the higher modules 12 and 14.
Describing the function of the network module 18 to control the message transferred to the subscriber module 12 and the retaining module 14 with reference to the flow chart of FIG. 2, the network module 18 analyzes the message in step 200 to determine in step 202 whether it is an error or normal. If it is an error, an error message is treated in step 204 and processing and transferring steps for the message are bypassed. Otherwise, a normal message is processed and formatted in step 206, and transferred in step 208 to the message conversion and distribution module 16, which again analyzes and format the formatted message to be accommodated to distribute it among the subscriber and retaining modules 12 and 14.
Conversely, describing the function of the network module 18 to control the message coming from the subscriber and retaining modules 12 and 14 with reference to the flow chart of FIG. 3, the message conversion and distribution module 16 analyzes and formats the message to be transferred to the network module 18, which in turn executes the steps 300 to 308 similar to those of FIG. 2 to transfer to the DLC module 20.
The conventional system as described suffers from the drawback that the message conversion and distribution module 16 requires the message exchange and corresponding protocol with the network module 18, which degrades the speed of processing data.